Cruz Lozano was arrested Tuesday after he turned himself in to U.S. authorities on separate charges for making terroristic threats against Hidalgo County (TX) Sheriff Lupe Trevino.

But before he surrendered, he offered an exclusive confession to Univision with details about, what he claims, was the day he murdered Terry during a firefight while he was on patrol on the U.S. Mexico border in Arizona.

Cruz Lozano is the second man to confess to Terry's murder. In October, Mexican national Manuel Osorio-Arellanes pleaded guilty in a first degree murder plea for Terry's murder. Osorio-Arellanes was shot during the gunfight and had been in custody since the night of the shooting.

Terry was shot during a firefight in December between border agents and five men who had sneaked into the country from Mexico for the purpose of robbing marijuana smugglers.

Cruz Lozano, who said he's killed "about 10" people, said he was one of the group that preyed on drug smugglers and undocumented immigrants when they encountered Terry and his partners.

"We were, well, with a drug shipment and when they surprised us there were people that started surrounding them and that's when we ambushed them," he said in Spanish to Univision.

"Unfortunately...there was no time for them to react."

Terry's death was a catalyst for uncovering the U.S. government's botched gun walking investigation known as "Operation Fast and Furious."

Two rifles bought by a gun-smuggling ring that was being monitored by the government's botched investigation were found at the shooting scene. The two guns were bought by 25-year-old man Jaime Avila Jr. who pleaded guilty in federal court to conspiracy and dealing guns without a federal license and was sentenced to nearly five years in federal prison.

Operation Fast and Furious was launched in 2009 to catch trafficking kingpins, but federal agents lost track of about 1,400 of the more than 2,000 weapons -- including AK-47s and other high-powered assault rifles.

Some of the guns purchased illegally with the government's knowledge were later found at crime scenes in Mexico and the U.S..

Authorities are still searching for three fugitives linked to the murder scene. Authorities have offered a $1 million reward for information leading to their capture.